As a candidate in 2008, Barack Obama emphatically stated that medical marijuana use was an issue best left to the states. One of the first promises he made as the newly elected president was that he was “not going to be using Justice Department resources to try to circumvent state laws.” This was even reiterated formally in the so-called Ogden memo of 2009, in which the Department of Justice instructed U.S. attorneys that federal enforcement should apply only to medical marijuana operations that were not in clear compliance with state law.Obama has since “clarified” those promises, but it still makes no sense that Matthew R. Davies, a business school graduate who set out in 2009 to create a medical marijuana dispensary that would be in full compliance with California law, is facing up to 15 years in prison — with a mandatory five-year sentence.This is just one more puzzling incident in the history of a president who not only made these promises but has also admitted to heavy recreational use of marijuana himself in his youth.